a. Competition: Humans compete with all organisms for space.
b. Parasitism: Humans have many parasites: head lice, ticks, tapeworms, etc.
c. Mutualism: We have mutualistic relationships with all domesticated plants/animals.
d. Commensalism: Pigeons thrive in metropolitan ecosystems without really
affecting humans (except for being mildly disgusting).
Answer:
The ventricles of the heart have thicker muscular walls than the atria. This is because blood is pumped out of the heart at greater pressure from these chambers compared to the atria. ... This is due to the higher forces needed to pump blood through the systemic circuit (around the body) compared to the pulmonary circuit.
Explanation:
The Human Heart — PT Direct
Answer: pro is one cell - archaebacteria, eubacteria
eukaryote is more than one - protista, fungi, plantae, animalia.
Explanation: